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-rw-r--r--fs/cramfs/uncompress.c106
1 files changed, 106 insertions, 0 deletions
diff --git a/fs/cramfs/uncompress.c b/fs/cramfs/uncompress.c
new file mode 100644
index 0000000..170832a
--- /dev/null
+++ b/fs/cramfs/uncompress.c
@@ -0,0 +1,106 @@
+/*
+ * uncompress.c
+ *
+ * Copyright (C) 1999 Linus Torvalds
+ * Copyright (C) 2000-2002 Transmeta Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (Version 2) as
+ * published by the Free Software Foundation.
+ *
+ * cramfs interfaces to the uncompression library. There's really just
+ * three entrypoints:
+ *
+ * - cramfs_uncompress_init() - called to initialize the thing.
+ * - cramfs_uncompress_exit() - tell me when you're done
+ * - cramfs_uncompress_block() - uncompress a block.
+ *
+ * NOTE NOTE NOTE! The uncompression is entirely single-threaded. We
+ * only have one stream, and we'll initialize it only once even if it
+ * then is used by multiple filesystems.
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <watchdog.h>
+#include <zlib.h>
+
+#if (CONFIG_COMMANDS & CFG_CMD_JFFS2)
+
+static z_stream stream;
+
+#define ZALLOC_ALIGNMENT 16
+
+static void *zalloc (void *x, unsigned items, unsigned size)
+{
+ void *p;
+
+ size *= items;
+ size = (size + ZALLOC_ALIGNMENT - 1) & ~(ZALLOC_ALIGNMENT - 1);
+
+ p = malloc (size);
+
+ return (p);
+}
+
+static void zfree (void *x, void *addr, unsigned nb)
+{
+ free (addr);
+}
+
+/* Returns length of decompressed data. */
+int cramfs_uncompress_block (void *dst, void *src, int srclen)
+{
+ int err;
+
+ inflateReset (&stream);
+
+ stream.next_in = src;
+ stream.avail_in = srclen;
+
+ stream.next_out = dst;
+ stream.avail_out = 4096 * 2;
+
+ err = inflate (&stream, Z_FINISH);
+
+ if (err != Z_STREAM_END)
+ goto err;
+ return stream.total_out;
+
+ err:
+ /*printf ("Error %d while decompressing!\n", err); */
+ /*printf ("%p(%d)->%p\n", src, srclen, dst); */
+ return -1;
+}
+
+int cramfs_uncompress_init (void)
+{
+ int err;
+
+ stream.zalloc = zalloc;
+ stream.zfree = zfree;
+ stream.next_in = 0;
+ stream.avail_in = 0;
+
+#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
+ stream.outcb = (cb_func) WATCHDOG_RESET;
+#else
+ stream.outcb = Z_NULL;
+#endif /* CONFIG_HW_WATCHDOG */
+
+ err = inflateInit (&stream);
+ if (err != Z_OK) {
+ printf ("Error: inflateInit2() returned %d\n", err);
+ return -1;
+ }
+
+ return 0;
+}
+
+int cramfs_uncompress_exit (void)
+{
+ inflateEnd (&stream);
+ return 0;
+}
+
+#endif /* CFG_FS_CRAMFS */